Color and motion animations for transparencies

ABSTRACT

For use on an overhead projector to give an illusion of motion, a transparency sheet bearing art work in the form of a grid is superposed on a relatively movable transparency sheet or web bearing a second or control grid. The lines or groups of lines of the art work grid and the second grid are parallel and both are at an angle to the direction of relative motion. On either sheet the lines may be of any appropriate color and may be made up of rows of dots. Dots of differing color in rows at different angles may be used. On either sheet, but not both, the lines are desirably arcuate and drawn on like radii about centers successively offset on a line parallel to the direction of relative movement, such arcuate lines being tangent to a construction line at the desired 45* angle to the direction of motion. On both sheets, the width or apparent width of respective lines is substantially identical with the width or apparent width of intervening spaces between the lines.

United States Patent Wright 1 June 6, 1972 COLOR AND MOTION ANIMATIONS FOR TRANSPARENCIES John S. Wright, 6115 North Lake Drive Court, Milwaukee, Wis. 53217 [22] Filed: Sept. 23, 1969 [21] Appl.No.: 860,356

[72] Inventor:

[52] US. Cl ..40/l06.53, 353/46 [51] Int. Cl. ..G09f 13/34 [58] Field of Search ...40/l06.5l, 106.52, 106.53,

Primary Examiner-Wm. H. Grieb Attorney-Wheeler, Wheeler & House [57] ABSTRACT For use on an overhead projector to give an illusion of motion, a transparency sheet bearing art work in the form of a grid is superposed on a relatively movable transparency sheet or web bearing a second or control grid. The lines or groups of lines of the art work grid and the second grid are parallel and both are at an angle to the direction of relative motion. On either sheet the lines may be of any appropriate color and may be made up of rows of dots, Dots of differing color in rows at different angles may be used. On either sheet, but not both, the lines are desirably arcuate and drawn on like radii about centers successively offset on a line parallel to the direction of relative movement, such arcuate lines being tangent to a construction line at the desired 45 angle to the direction of motion. On both sheets, the width or apparent width of respective lines is substantially identical with the width or apparent width of intervening spaces between the lines.

13 Claims, 7 Drawing Figures COLOR AND MOTION ANIMATIONS FOR TRANSPARENCIES BACKGROUND OF INVENTION It is known in the prior art to provide assemblages of relatively movable transparencies to give an appearance of motion. Some of the difficulties experienced in prior devices for this purpose are the following:

1. In some instances,-everything on the transparency bearing the art work is given the appearance of motion whereas this is undesirable as to certain features such as printing.

2. In some instances, the effect is partially lost because it is too fleeting or continuous or unidirectional.

3. In some instances, the prior art does not provide adequately for relative movement between the transparencies at precisely the desired angle, angle being important.

4. In some instances, the projected images are not sharp because of spacing between the planes of the grids of the relatively movable transparencies.

5. In some instances, desirable effects are lost by having proximate dots of differing colors which are not in conformity with optimum regularity of placement on lines of desired angles.

The most pertinent prior art known to me will be found in the following U.S. Pat. Nos.: 2,482,947; 2,918,743; 2,624,142; and 3,235,987.

SUMMARY OF INVENTION Art and control grid transparencies designed for relative movement in a well-defined relative direction both have grid lines drawn at an angle to the direction of relative motion and preferably in substantial face contact in immediately proximate planes. Either or both sets of lines may be printed to be continuous or may comprise rows of closely adjacent dots. To give maximum action the grid lines comprising the art work or picture to which motion is to be imparted preferably include groups of parallel lines wherein the lines of each successive group are slightly offset from the lines of the next preceding group, the direction of offset being at right angles to the direction of the parallel lines, the latter being parallel to the direction of motion. As already stated, it is preferred that the weight or width of respective lines be identical with each other and that the intervening areas between lines shall be of corresponding width.

In color work using this invention, dots of color are printed on the art transparency in rows which vary in angle for each color. The relative motion of the control grid thereupon yields interesting tone fluctuation.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a diagrammatic perspective view showing an art grid sheet and a relatively movable control grid sheet or web or the stage of an overhead projector.

FIG. 2 is a fragmentary bottom plan view of an art work sheet.

FIG. 3 is a plan view of the control grid sheet.

FIG. 4 is a greatly enlarged view of a portion of FIG. 2.

FIG. 5 is a greatly enlarged view of a portion of FIG. 2 or FIG. 3 showing grid lines which are made up of rows of dots as distinguished from continuous lines.

FIG. 6 is a diagrammatic plan view showing on a greatly enlarged scale the relative positions of dots of differing colors as preferred to be used when the invention is to be used in color.

FIG. 7 is a greatly enlarged fragmentary view in section on line 7-7 of FIG. I. I

DETAILED DESCRIPTION As an illustrative example of one embodiment of the invention, I have shown an art work sheet 10 comprising a page of a transparency storage and display book 12 supported on the stage of an overhead projector 14 as disclosed in my copending application Ser. No. 748,255, filed July 9, 1968.

The control grid sheet or web 16 underlies the art work sheet 10 and is mounted for relative movement beneath the art work sheet to product the illusion of motion sought by the present invention. For sharpness it is preferred that the grids be in face contact. At least the transparencies should not be spaced.

The control grid sheet 16 may be used with any of the art work sheets of the display book 12. It may be advanced in any desired manner. It has been found practicable to advance it by means of motor 18, retraction being manual. The shaft 19 driven by the motor carries feed rolls 20 engaged with sheet 16, the sheet being held to the feed rolls by spring pressed buttons 22 of "Teflon or the like which have little frictional resistance to the manual return of the grid sheet. In practice, the grid sheet moves very slowly and the relative dimensions indicated in FIG. 1 will permit the illusion of motion to be continued for a period of approximately 3 minutes without resetting control sheet 16.

In accordance with the invention, the art work on the sheet 12 preferably includes an outline 23 and a grid comprising rows of parallel lines 24 which are preferably divided into groups 25 wherein the lines 24 of each group are slightly offset from the corresponding lines of adjacent groups 25, the direction of offset preferably being at right angles to the direction of the respective lines (FIG. 4). The lines are desirably of equal width or weight" and this width also corresponds in width to the clearance 26 between lines.

I have found it desirable that the direction of the several lines shall be at an angle to the direction of relative movement between the art work sheet and the control grid sheet. For the purposes of this disclosure, the direction of relative movement is here represented by the direction of the free margin 30 of the art work sheet 10. The pins 32 which locate the art work sheet on the stage are spaced in that direction and are also used in the present embodiment as a convenient means of guiding the relatively movable control grid sheet or web 16.

The control grid sheet 16 has grid lines 34 which are desirably drawn upon arcs of equal radius 36, the centers of such arcs being shown at 38 uniformly spaced upon a construction line 40 which is parallel to the direction of relative motion as here represented by the line 30. (The radii 36 are greatly foreshortened in FIG. 3.) The illustrated radii are construction lines on which the arcuate grid lines are respectively centered. Each radius 36 is desirably at right angles to the construction line 42 which, in turn, is at 45 to the direction of relative motion and is therefore parallel to the grid lines 24 on the art work sheet.

It is true both of the grid lines 24 on the art work sheet and the grid lines 34 of the control grid sheet that these lines may be made of rows of dots instead of being made continuous. This is indicated in FIG. 5 which shows the line 46 made up of a series of dots 48. It is to be understood that where lines or dots are referred to, it is only necessary that there be contrast between the lines or dots and the background. It is immaterial whether the background is darker or lighter. Whether a given grid line is continuous or whether it is made up of dots, the apparent width of all grid lines should desirably be the same and should also correspond to the spacing between such lines.

In another embodiment of the invention, process color is achieved by means of rows of dots of color. Process color refers to the optical illusion of color created bythe projection of two different colors simultaneously on the screen to produce an illusion of a third color. It is well-known in printing that different colors can be created by using the three primary colors red, yellow and blue. This is achieved by printing dots of different color closely adjacent to each other. The same efiect can be created by projecting the dots of different colors on a screen.

FIG. 6 shows an enlarged section of one of the grids in which the grid is made up of rows of colored dots. From the base line 50, the construction lines 52 are drawn at a 45 angle; the construction lines 54 are drawn on a angle; and the construction lines 56 are drawn at an angle of Where the lines 52 and 54 intersect, there are dots 58 of one color.

Where the lines 54 and 56 intersect, there are dots 60 of another color.

Assuming that one set of dots is red and another yellow, an orange shade will appear on the screen. Assuming one set of dots is red and another blue, a purple shade will appear on the screen. Assuming that one set of dots is blue and the other yellow, a green shade will appear on the screen.

If it be desired that the projected light results from the combination of three separate colors, it is possible to draw addi tional angular lines (for example, at 75) to detemiine the location of the required third set of dots.

Since all of the rows are angularly related to each other and to the direction of relative movement of the control grid 16,

the color effects will fluctuatejsubject to the control of such grid when there is relative movement between the control grid and the grid which comprises the colored dots.

I claim:

1. A combination of relatively movable transparencies for use in a projection system to give the projected image an illusion of motion, each of the said transparencies comprising a grid, one of said grids comprising an art grid and the other a control grid, and means for guiding one of said transparencies for movement in a predetermined direction with respect to the other, both grids having lines at an acute angle to the direction of relative motion.

2. A combination according to claim 1 in which each grid comprises lines and intervening spaces, the width of the respective lines and the respective spaces being substantially uniform in both grids.

3. A combination according to claim 1 in which the lines of one of said grids are arcuate and the lines of the other of said grids are at an angle approximating 45 to said direction.

4. A combination according to claim 3 in which said arcuate lines are respectively tangent to lines which are angularly related to the direction of relative movement between the control grid and the art grid.

5. A combination according to claim 4 in which the lines of one of said grids are arcuate and substantially centered on tangential construction linesat approximately 45 to direction of relative motion.

6. A combination of relatively movable transparencies for use in a projection system to give the projected image an illusion of motion, each of the said transparencies comprising a grid, one of said grids comprising an art grid and the other a control grid, and means for guiding one of said transparencies for movement in a predetermined direction with respect to the other, both grids having lines at an acute angle to the direction of relative motion, said lines of at least one of said grids comprising rows of dots with intervening background color contrasting with said dots, one grid comprising rows of dots of one color, said rows being at a predetermined angle with respect to I direction of relative movement between said grids, and means providing second rows of dots of different color and drawn at an angle to the first mentioned rows of dots.

7. The combination with a book of transparencies comprising leaves bearing art work for projection, the art work being comprised of groups of grid lines which are substantially parallel, the grid lines of each group being slightly offset laterally with respect to the grid lines of an adjacent group, and a control grid having a set of lines at the same angle as the grid lines on said leaves, the control grid being mounted for movement with respect to successive leaves respectively associated therewith.

8. A combination according to claim 7 in which the lines of one of said grids are arcuate. v

9. A combination according to claim 7 in which the control grid comprises a web having means guiding it for movement beneath any leaf of said book superimposed thereon.

1 10. A combination according to claim 9 in further combination with means for slowly advancing the control grid web, said means being impositive in its action on said web whereby said web may be manually retracted from any position of advance.

1 l. A projector comprising in combination a stage, a projection lens, a light source, a transparency having means mounting it for movement in a predetermined direction across the stage and provided with groups of lines constituting a control grid, the lines of each group being disposed at an acute angle to said direction, a second transparency in superimposed relation to the first transparency and having a releasable means for holding it fixed with respect to the stage and provided with an art grid comprising groups of lines substantially parallel to each other and also at an acute angle to the said direction of movement of the first transparency respecting the stage, the lines of respective groups being of uniform width substantially identical to the spacing between lines.

12. A projector according to claim 11 in which the second transparency comprises a leaf of a book in which other like transparencies are bound and which are selectively movable to and from operative positions on said stage for coaction with the first mentioned transparency on which the control grid is provided.

13. A projector according to claim 1 l in which the grid lines on one of said transparencies comprise rows of dots and in which the dots are of differing colors, the rows of dots of one color being at a different angle to the direction of control grid movement than the rows of dots of another color. 

1. A combination of relatively movable transparencies for use in a projection system to give the projected image an illusion of motion, each of the said transparencies comprising a grid, one of said grids comprising an art grid and the other a control grid, and means for guiding one of said transparencies for movement in a predetermined direction with respect to the other, both grids having lines at an acute angle to the direction of relative motion.
 2. A combination according to claim 1 in which each grid comprises lines and intervening spaces, the width of the respective lines and the respective spaces being substantially uniform in both grids.
 3. A combination according to claim 1 in which the lines of one of said grids are arcuate and the lines of the other of said grids are at an angle approximating 45* to said direction.
 4. A combination according to claim 3 in which said arcuate lines are respectively tangent to lines which are angularly related to the direction of relative movement between the control grid and the art grid.
 5. A combination according to claim 4 in which the lines of one of said grids are arcuate and substantially centered on tangential construction lines at approximately 45* to direction of relative motion.
 6. A combination of relatively movable transparencies for use in a projection system to give the projected image an illusion of motion, each of the said transparencies comprising a grid, one of said grids comprising an art grid and the other a control grid, and means for guiding one of said transparencies for movement in a predetermined direction with respect to the other, both grids having lines at an acute angle to the direction of relative motion, said lines of at least one of said grids comprising rows of dots with intervening background color contrasting with said dots, one grid comprising rows of dots of one color, said rows being at a predetermined angle with respect to direction of relative movement between said grids, and means providing second rows of dots of different color and drawn at an angle to the first mentioned rows of dots.
 7. The combination with a book of transparencies comprising leaves bearing art work for projection, the art work being comprised of groups of grid lines which are substantially parallel, the grid lines of each group being slightly offset laterally with respect to the grid lines of an adjacent group, and a control grid having a set of lines at the same angle as the grid lines on said leaves, the control grid being mounted for movement with respect to successive leaves respectively associated therewith.
 8. A combination according to claim 7 in which the lines of one of said grids are arcuate.
 9. A combination according to claim 7 in which the control grid comprises a web having means guiding it for movement beneath any leaf of said book superimposed thereon.
 10. A combination according to claim 9 in further combination with means for slowly advancing the control grid web, said means being impositive in its action on said web whereby said web may be manually retracted from any position of advance.
 11. A projector comprising in combination a stage, a projection lens, a light source, a transparency having means mounting it for movement in a predetermined direction across the stage and provided with groups of lines constituting a control grid, the lines of each group being disposed at an acute angle to said direction, a second transparency in superimposed relation to the first transparency and having a releasable means for holding it fixed with respect to the stage and provided with an art grid comprising groups of lines substantially parallel to each other and also at an acute angle to the said direction of movement of the first transparency respecting the stage, the lines of respective groups being of uniform width substantially identical to the spacing between lines.
 12. A projector according to claim 11 in which the second transparency comprises a leaf of a book in which other like transparencies are bound and which are selectively movable to and from operative positions on said stage for coaction with the first mentioned transparency on which the control grid is provided.
 13. A projector according to claim 11 in which the grid lines on one of said transparencies comprise rows of dots and in which the dots are of differing colors, the rows of dots of one color being at a different angle to the direction of control grid movement than the rows of dots of another color. 